1. Technical Field
The present invention relates to a digital broadcasting system which has input devices and output devices connected in a network form, and more particularly, to a broadcasting system which can monitor the system for operating conditions.
2. Description of Related Art
FIG. 6A generally illustrates a conventional broadcasting apparatus. In this broadcasting apparatus, a plurality of, for example, four input devices 11-14 are connected to a plurality of, for example, four output devices 21-24 through a controller 30 called a “matrix controller.” Here, the input device refers to an arbitrary audio signal feeding device including a sound source device such as a CD player, a cassette deck, an audio file device and the like, and a microphone terminal, while the output device refers to an audio output device including an amplifier which has a speaker connected to the output side thereof. In a building and the like, the input devices 11-14 and output devices 21-24 are installed in each floor, a management room, or the like.
The controller 30 controls which of the input devices 11-14 inputs sound and delivers the sound to which of the output devices 21-24. For implementing this control, the controller 30 contains a table which represents the relationships between the input devices 11-14 and output devices 21-24 in a matrix form, and stores a plurality of destinations in groups. An example of this table is shown in FIG. 6B. A black circle in the table indicates which of the output devices generates sound delivered from which of the input devices. For example, sound delivered from the input device 11 is output from the output devices 21 and 22, while sound delivered from the input device 12 is not output from any output device. In this event, the output devices 21 and 22 are registered as Group 1, so that the controller 30 selects Group 1 when it receives sound, for example, from the input device 11, thereby causing the output devices 21, 22 to output the sound from the Input device 11. In this way, the controller 30 stores in a one-to-one correspondence the relationships between input devices and groups of output devices which output sound from an associated input device, and is responsive to a request from an input device to instruct output devices registered as included in a group corresponding to the input device to output sound from the input device.
When priorities are set to broadcast contents, even if a certain program is on air, this program is switched to a program with a higher priority when the higher priority program is started. A program with a lower priority may be, for example, a BGM (background music) program, while a calling program, for example, is set a higher priority. While such priorities may be set for each input device, an input device may be provided with a function of selecting a priority in accordance with broadcast contents.
As described above, it is the controller 30 that specifies a destination and a group, but alternatively, the input devices 11-14 may be each provided with a controller for specifying an output device which is the destination. FIG. 7 illustrates the appearance of an input device which contains such a controller. In FIG. 7, an input device 40 comprises a microphone 42 implanted on a housing 41; and a broadcasting switch 43, group selection switches 44, and indicators 45 arranged in the housing 41. The broadcasting switch 43 is a switch for indicating the start and end of broadcasting. The group selection switches 44 are associated with respective groups, so that a switch corresponding to a group which should deliver input sound is depressed for broadcasting. As one of the group selection switches 44 is depressed, an indicator 45 associated therewith is lit to indicate a group which is currently on air. The controller in FIG. 7 is generally used to specify and start a desired program, and a lit one of indicators 45 permits the operator to recognize of which of the groups a currently broadcast program is associated with.
As described above, the controller 30 illustrated in FIG. 6A simply controls the relationships between input devices and output devices in accordance with a matrix table, and the controller 40 in FIG. 7 is similar in simply selecting a destination and indicating a group currently on air. In other words, the input devices 11-14 simply deliver an audio signal to an output device specified thereby or by the controller 30. In a modification to the foregoing, a request may be made from an output device to an input device, such that the input device delivers an audio signal in response to the request. However, in any case, the conventional broadcasting apparatus fails to notify the user of the priority of the broadcasting, specifically, which has a higher priority, a currently broadcast program or a program to be broadcast by the user from now on, thus giving rise to a problem that the user cannot know whether or not his program can be broadcast.